feat: add HDRI

1 files changed, 33 insertions, 0 deletions

diff --git a/assets/shaders/equirect_to_cubemap.glsl b/assets/shaders/equirect_to_cubemap.glsl
new file mode 100644
index 0000000..2b99c9b
--- /dev/null
+++ b/assets/shaders/equirect_to_cubemap.glsl
@@ -0,0 +1,33 @@
+#type vertex
+
+#version 330 core
+layout (location = 0) in vec3 aPos;
+out vec3 WorldPos;
+uniform mat4 projection;
+uniform mat4 view;
+void main()
+{
+    WorldPos = aPos;
+    gl_Position = projection * view * vec4(WorldPos, 1.0);
+}
+
+#type fragment
+
+#version 330 core
+out vec4 FragColor;
+in vec3 WorldPos;
+uniform sampler2D equirectangularMap;
+const vec2 invAtan = vec2(0.1591, 0.3183);
+vec2 SampleSphericalMap(vec3 v)
+{
+    vec2 uv = vec2(atan(v.z, v.x), asin(v.y));
+    uv *= invAtan;
+    uv += 0.5;
+    return uv;
+}
+void main()
+{
+    vec2 uv = SampleSphericalMap(normalize(WorldPos));
+    vec3 color = texture(equirectangularMap, uv).rgb;
+    FragColor = vec4(color, 1.0);
+}